Roof Curb Options for HVAC Systems

roof top HVAC system in MOAmerican Services HVAC installation service near Ladue knows that roof curb is a metal sheet made to fit around a chimney or vertically aligned vent on your roof, otherwise known as a flashing. The roof curb is either one single metal sheet with a beveled or curved bottom lip. A roof curb extends up vertically in one piece. This products primary function is channeling water away from the seam formed between the roof and the vertical chimney or vent.

According to its webpage, Thybar has been in the business of making sheet metal products for over half a decade.  According to Greg Mazurkiewicz’s recent article on, “these insulated curbs for metal buildings are custom designed to accommodate any rooftop equipment and to conform to any roof pitch, the company says. The curbs are fabricated using 14- and 18-gauge AZ-55 Galvalume material with welded construction, built-in diverter, and integral conforming notches for compatibility with Galvalume roof panels and a watertight seal, says the company. Factory-installed rigid insulation, 1 1/2-in. thick and 3 lb density, is included”.

Manufacturers, like Thybar, put out non-insulated pre-fabricated roof curbs as well. Both types come styled in different ways. Insulated and non-insulated curbs for insulated and non-insulated roof decks come with a 3-inch cant and variable step to match up with the thickness of the deck insulation. Varying degrees of customization and specification is available.

Associated optional features with these building components are numerous. They include height addition specifications, heavier metal gauges, aluminum construction and galvanized stell or aluminum liners. There are also options that include; factory installed burglar bars and construction to fit both single and double roof pitches. Additionally there are chemically treated wood nailers as well as overhanging wood nailers on certain groups of curbs.